Serum IGF-BP2 strongly moderates age's effect on cognition: a MIMIC analysis

Area of Science:

• Neuroscience
• Gerontology
• Biomedical Engineering

Background:

• Cognitive decline is a significant aspect of aging.
• Identifying specific markers for age-related cognitive impairment is crucial for early diagnosis and intervention.
• Existing models often do not fully isolate dementia-specific cognitive variance.

Purpose of the Study:

• To develop and validate a novel metric, cognitive correlates of aging (cAGE), to quantify dementia-relevant cognitive variance.
• To investigate the mediating role of cAGE in the relationship between aging and dementia severity.
• To explore the association between cAGE, serum insulin-like growth factor binding protein 2 (IGF-BP2), and cognitive function in older adults.

Main Methods:

• Structural equation modeling was employed to distinguish dementia-relevant cognitive variance.
• A cAGE metric was constructed as a proxy for age-related cognitive changes.
• The association between cAGE, IGF-BP2, and cognitive function was analyzed, controlling for demographic and clinical factors.

Main Results:

• The cAGE metric largely mediated the effects of age on dementia severity, as measured by the Clinical Dementia Rating Scale Sum of Boxes.
• cAGE demonstrated high diagnostic accuracy (AUC = 0.96) for distinguishing Alzheimer's Disease from controls.
• IGF-BP2's negative impact on cognition was predominantly mediated through cAGE, independent of various confounding factors.

Conclusions:

• The cAGE metric effectively captures age-related cognitive changes relevant to dementia.
• IGF-BP2 plays a significant role in age-specific cognitive decline, acting through the cAGE pathway.
• Modulating IGF-BP2 function presents a potential therapeutic strategy for ameliorating age-associated cognitive impairments.